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41.
针对目前铁道部有关加强行车安全的文件与设计概算编制规定不协调的问题,笔者提出了自己的看法. 相似文献
42.
SONG Zhi-ming KANG Feng-ju TANG Kai and CHU Yan-jun Marine College Northuxstern Polytechnical University Xi'''' an China 《船舶与海洋工程学报》2003,2(2):40-45
Realistic simulation of underwater scene is always difficult because of the special and complex vision effects in underwater space. Seabed is an important part of underwater environment. This paper describes the methods for seabed scene simulation based on OpenGL. It includes construction of fluetuant terrain based on the random sinusoidal algorithm, simulation of seabed flicker effect by means of circular texture mapping and generation of turbidity effect by using fog techniques. For the application based on the leading high level 3D development environment-Vega, underwater scene simulation is still a difficulty since there is no module for it. Based on the analysis of Vega software and the research on seabed scene simulation methods, a Vega extending module named “Underwater Space” was created through developing module class and extending lynx interface. The module class was designed through developing DLL written in C . The Lynx was extended through developing keyword configure file, GUI configure file and lynx plug-in DLL. The problem that Vega can‘t simulate underwater space, is elementarily resolved. The results show that this module is efficient, easy using, and the seabed scene images am vivid. 相似文献
43.
针对异形屋面结构中经常采用的不规则形状折梁设计,施工过程中充分利用AutoCAD三维立体图的方式,完成不规则折梁钢筋的翻样,化解翻样难度,提高翻样效率,保证翻样精度,同时阐述了如何解决施工过程中遇到的安装问题。 相似文献
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45.
Development of hot stamped center pillar using form die with channel type indirect blank holder 总被引:1,自引:0,他引:1
H. S. Choi B. M. Kim K. J. Nam S. Y. Ha S. H. Cha C. G. Kang 《International Journal of Automotive Technology》2011,12(6):887-894
The hot stamping process has been used in the automotive industry to reduce the weight of the body-in-white and to increase
passenger safety via improved crashworthiness. However, defects such as fracture and wrinkle occur when hot stamping is performed
using a conventional drawing or forming method. In this study, a channel-type indirect blank holder (CIBH) is proposed to
develop a high-strength center pillar in form-type hot stamping, so that the aforementioned drawbacks are overcome. This type
of blank holder plays an important role in reducing severe wrinkling at the flange; such wrinkling leads to folding after
the completion of form-type hot-stamping. First, we investigated the effect of the channel shape on the indirect blank holding
force by using a simplified two-dimensional plane-strain stamping process. Second, we selected the slope angle and corner
radius of the channel as the main shape parameters by finite element analysis and artificial neural network (ANN). It is known
that fracture at the hot formed wall and wrinkle at the flange are significantly affected by the slope angle of the channel,
and the appropriate value for eliminating fracture and wrinkle is determined to be 99°. By performing hot stamping using a
form die with the selected channel, we can manufacture a high-strength center pillar without wrinkle and fracture. 相似文献
46.
When using limited funds on bicycle facilities, it would be helpful to know the extent to which a new facility will be used. If a bicycle lane is added to a street, how many bicyclists will no longer use the adjacent sidewalk? If a separate bicycle path is constructed, how many bicyclists will move from the street or sidewalk? This study seeks to identify factors that explain a bicyclist’s choice between available facility choices—off-street (sidewalk and bicycle path) or on-street (bicycle lane and roadway). This paper investigates these issues through a survey of bicyclists headed to Purdue University in West Lafayette, IN, USA. The first data collected to address these questions were “site-based”. Bicyclists were interviewed on campus at the end of their trips and asked which part of the cross-sections along their routes they had used—on-street or off-street. The characteristics of a particular cross-section of street right-of-way were then compared against the characteristics of each bicyclist and his/her observed choice of street, sidewalk, lane, or path. Later, “route-based” serial data were also added. The study developed a mixed logit model to analyze the bicyclists’ facility preferences and capture the unobserved heterogeneity across the population. Effective sidewalk width, traffic signals, segment length, road functional class, street pavement condition, and one-way street configuration were found to be statistically significant. A bicycle path is found to be more attractive than a bicycle lane. Predictions from the model can indicate where investments in particular bicycle facilities would have the most desirable response from bicyclists. 相似文献
47.
分析在覆盖区域大、地质复杂的条件下,中国高速铁路工务工程"高可靠性、高稳定性、高平顺性"的技术特点,针对路网规模大、运营速度高、行车密度大的特征,围绕高速铁路运营的"安全、舒适、秩序",研究提出工务设备管理维护模式,在高速铁路安全运营实践的基础上,提出适合中国高速铁路工务设备检查、监控、修理的对策。 相似文献
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<正>五羊——本田优客(上接2014年第1期)五羊——本田优客有2款车型,分别是普通款的(STD)型和集中制动款的(HGBS)型,图5为普通型的电起动电路原理图。蓄电池正电源通过主保险后,由输出端红/白色(R/W)线进入点火保险和电源继电器的触点一端。电源由点火保险输出端黑/蓝色(B1/Bu)线进入电门锁,打开电门锁后,电源由黑/白色(B1/W)线进入起动继电器的线圈一端、ECM和电源继电器的线圈一端。电源继电器线圈另一端为固定搭铁的绿色线,电源继电器线圈得电吸合触点,电源由触点另一端红/黄色(R/Y)线进入信号保险。 相似文献
50.
为探讨增殖细胞核抗原 ( Proliferating cell nuclear antigen,PCNA)在胃癌的表达与淋巴结转移及预后的关系 ,采用免疫组化法 ( ABC法 )测定 94例胃癌石蜡包埋标本。结果 :1胃粘膜不同病理状态下 PCNA指数差异显著 ( P <0 .0 1 ) ;2PCNA指数同患者的性别和年龄无关 ( P >0 .0 5 ) ,与肿瘤的生长方式、组织类型、浆膜层受侵与否、淋巴结转移与否和临床分期关系密切 ( P <0 .0 5 ) ;3PCNA指数与胃癌的预后密切相关 ( P <0 .0 5 ) ,弱级 ( 1~ 2级 )表达的患者预后较好 ,提示 PCNA检测可作为判断胃癌生物学行为和预后的一项良好指标。 相似文献